METHOD OF PRODUCTION OF BRANCHED POLYMETHYLPHENYLSILOXANE LIQUIDS Russian patent published in 2024 - IPC C08G77/06 

FIELD: chemical technology.

SUBSTANCE: invention relates to the production of organosilicon compounds used as bases for heat-resistant and radiation-resistant oils and can be used in the development of technology for their production with a high yield of branched polyorganosiloxanes. The proposed method of production of branched polymethylphenylsiloxane liquids involves the polycondensation of alkoxysilanes in an active medium, which is anhydrous acetic acid, while the polycondensation is carried out in the presence of a catalyst selected from the following range: trimethylchlorosilane, methyldiphenylchlorosilane, acetyl chloride; a mixture of methyldiphenylethoxysilane, methylphenyldialkoxysilane and organotrialkoxysilane of general formula RSiOAlk₃, where R is CH₃ and/or C₆H₅, Alk-alkyl C₁-C₂ in a molar ratio of 1 to 1–2.5 and 0.5–1.5 is used as alkoxysilanes, the total amount of alkoxysilanes and anhydrous acetic acid in a molar ratio is from 1–1.8 to 1–3, the amount of catalyst is from 0.05 to 3 wt.% relative to the total amount of alkoxysilanes.

EFFECT: method makes it possible to obtain new polymethylphenylsiloxane liquids with a branched molecular structure, terminal methyldiphenylsilyl groups, and free of residual alkoxy and silanol groups.

1 cl, 2 dwg, 3 ex